Average Temperatures for Large US Cities in September

Average temperatures for the month of September in the largest US cities are listed below in degrees Fahrenheit and Celsius.

The tables give the normals for maximum and minimum temperatures based on weather data collected from 1981 to 2010 by the NOAA National Climatic Data Center of the United States.

Average high temperatures for major US cities during September range from 70 degrees Fahrenheit (21 degrees Celsius) in San Francisco to 100 °F (38 °C) in Phoenix. Temperatures this month are especially comfortable in cities such as New York and Philadelphia where the days are usually around 75 °F (24 °C) and the nights average about 60 °F (16 °C).